A non-clustered index is stored at one place and table data is stored in another place.
A table can have multiple non-clustered index in a table.
A non-clustered index in SQL Server is a database index that improves
query performance for specific columns without altering the physical
order of data in the table. It creates a separate data structure
containing indexed columns and references to the corresponding data
rows, enabling faster data retrieval for queries involving those
columns. Unlike clustered indexes, multiple non-clustered indexes can be
created on a single table, allowing optimization of various query
patterns.
